My sensor went with my coolant reservoir bottle due to the intense heat we have been having lately. I also lost alternator as well. The Tech at the dealership told me they are replacing a ton reservoir bottles and alternators of all Mazda models right now.

 

Just replaced the coolant bottle on my2007. Not hard to do, but I would recommend taking the air intake out as well as the lower tray for the intake. It will give you more room to connect the hoses back on the new bottle.

Basically there's a magnet (float) in the bottle that seems to get stuck due to gunk and grim buildup. I don't think that rinsing the bottle will clean it out much since the float is in a sub-chamber in the bottle. When I compared the old bottle and new bottle, it was obvious that the float slides much smoother in the new bottle. You can feel it getting stuck in the old bottle.

 

^...........wrong, but close!

https://www.rx8club.com/series-i-trouble-shooting-95/coolant-bottle-greatest-secrets-revealed-182793/

At least in 99% of the cases. 1% chance if you had mud in there.

 

My 2004's light always comes on I've gotten it checked and all is normal so Ive come to a conclusion That this faulty coolant sensor issue is a commen and harmless one unless you really do need coolant because those bad boys get hotter than hell!!

 

Lurker turned poster...

I called my local Mazda mechanic and mentioned the Stuck sensor in the bottle, since mine comes on every time I even think about pressing the gas, and he told me the bottle replaced runs about $330.00 -- BUT -- There is a 50/50 chance that a CLIP will break and then it turns into a $1200.00 job because he will have to replace the Radiator as well....

Was I fed a line of BS?

If this true then I am considering just buying a new (non-stock) Radiator and Bottle and was wondering if someone makes a bottle that won't exhibit this problem.

2006 RX8 Shinka 45,000 Miles

 

It's not a clip - it's a hose nipple on the radiator. IMHO, if the dealer replaces the bottle and breaks the radiator, that should be on the dealer's head. The bottle TSB describes the right procedure to avoid breaking the rad.

Mazda makes a new bottle that fixes the problem. Check out Mazurfer's thread. Or just pull the plug - that does a really nice job of turning the light off.

Ken

 

Guys is it possible to just replace the sensor without buying a whole new coolant tank???

 

Thanks for the advice. I will try reaching back out to the dealer and ask them to work on it and be the responsible party if something goes wrong. If they won't someone will.

Thanks for the advice.

 

It's not really the sensor that's the problem.. it's the float inside the bottle that gets stuck closed when it shouldn't. It's pretty sealed up in there, I won't try it unless you have no choice in the matter. To do it, you would have to saw it in half, replace the middle bits with parts you scrapped out of another bottle (or try rigging it with some foam or something) and then glue it back together in such a way that it held pressure as well as it did when it was in 1 piece. If you get it wrong you risk air in your coolant system, which is very bad. If you get it right you ... can make a fortune doing it for for all us Mazda owners. :P

 

Thx ASeitz...

 

There's a post somewhere on this site by someone who cut a hole in the tank just big enough to pull the float out, replaced it with a wine bottle cork, then fixed the hole with a bolt, some rubber gasket material, and a couple of fender washers.

If you get it wrong, you no longer have a pressurized cooling system.

Ken

 

I just got my rx8 and i dont no much about it, i am on a budget so i can pay the car and the insurance so i will need some help. I wanted to know what are the proper steps to flushing the radiator and what type of coolant would be the best to throw in it and what the mixture might be. The coolant light only comes on when i am in the high revs or when im going 75 or higher.

 

Post #1...Welcome!

There's a DIY on changing the coolant. Use a name brand coolant, diluted 50/50 or 55/45. Stick to whatever color is already in there, unless you like black.

IMHO, if you also spend time browsing the DIY section you'll learn everything you need to know about mainting your car. At least that's how it worked for me.

Since you've found this thread, you already know that the coolant light is not important, and should be treated as an entertainment rather than a problem.

Ken

 

What is the best coolant for my mazda 2003 rx8?

 

most people with this problem keep it unplugged

 

Just disconnect the sensor. It's useless in this case besides that eyesore it gives you.

 

Replying to a post from 2010.